Medication
Milligrams to Grams Conversion Chart for Common Medications
· Updated · 3 min read
In short
Common tablet strengths convert simply: 250 mg is 0.25 g, 500 mg is 0.5 g, and 1,000 mg is 1 g. The chart below covers the strengths seen most often on packaging so a prescription written in grams can be matched against a box printed in milligrams.
On this page
A unit reference, not a dosing guide
This chart converts units. It says nothing about what dose is appropriate, how often anything should be taken, or whether two products are interchangeable. Those questions belong to a pharmacist, doctor or nurse, and the product's own label always takes precedence.
Tablet strengths are printed in milligrams almost without exception, while prescriptions, clinical references and some packaging occasionally use grams. When the two do not match, the conversion is straightforward — but it is worth having the common values to hand.
The rule, in one line
Key takeaway
Divide milligrams by 1,000 to get grams. Multiply grams by 1,000 to get milligrams. 1 g = 1,000 mg exactly.
Common tablet strengths in grams
These are the strengths that appear most frequently on packaging, across many different medicines.
| Strength (mg) | In grams | Written as |
|---|---|---|
| 5 mg | 0.005 g | Five thousandths of a gram |
| 10 mg | 0.01 g | One hundredth of a gram |
| 20 mg | 0.02 g | Two hundredths of a gram |
| 25 mg | 0.025 g | — |
| 50 mg | 0.05 g | One twentieth of a gram |
| 75 mg | 0.075 g | — |
| 100 mg | 0.1 g | One tenth of a gram |
| 125 mg | 0.125 g | One eighth of a gram |
| 200 mg | 0.2 g | One fifth of a gram |
| 250 mg | 0.25 g | One quarter of a gram |
| 300 mg | 0.3 g | — |
| 400 mg | 0.4 g | — |
| 500 mg | 0.5 g | Half a gram |
| 600 mg | 0.6 g | — |
| 750 mg | 0.75 g | Three quarters of a gram |
| 800 mg | 0.8 g | — |
| 875 mg | 0.875 g | — |
| 1,000 mg | 1 g | One gram |
| 1,500 mg | 1.5 g | One and a half grams |
| 2,000 mg | 2 g | Two grams |
Milligrams → Grams
0.5g
500 mg = 0.5 g
Both sides weigh exactly the same — only the unit changes.
For any strength not listed, enter it here — the result appears as you type.
Going the other way
When a prescription or reference is written in grams and the packaging is in milligrams, multiply by 1,000.
| Amount (g) | In milligrams |
|---|---|
| 0.05 g | 50 mg |
| 0.1 g | 100 mg |
| 0.125 g | 125 mg |
| 0.25 g | 250 mg |
| 0.5 g | 500 mg |
| 0.75 g | 750 mg |
| 1 g | 1,000 mg |
| 1.5 g | 1,500 mg |
| 2 g | 2,000 mg |
| 3 g | 3,000 mg |
Multiple tablets
Adding up identical tablets is simple multiplication, and the total often crosses conveniently into whole grams — which is a common source of confusion when a total is quoted in grams but the box is in milligrams.
| Strength | ×2 | ×3 | ×4 |
|---|---|---|---|
| 250 mg | 500 mg (0.5 g) | 750 mg (0.75 g) | 1,000 mg (1 g) |
| 500 mg | 1,000 mg (1 g) | 1,500 mg (1.5 g) | 2,000 mg (2 g) |
| 200 mg | 400 mg (0.4 g) | 600 mg (0.6 g) | 800 mg (0.8 g) |
| 100 mg | 200 mg (0.2 g) | 300 mg (0.3 g) | 400 mg (0.4 g) |
Arithmetic is not permission
That two 500 mg tablets total 1 g is a fact about numbers. Whether taking two is appropriate is a completely separate question determined by the product's instructions and the individual's circumstances.
Micrograms on medicine labels
Some medicines are dosed in micrograms — certain thyroid, hormone and inhaled products among them. The same factor of 1,000 applies one rung further down.
| Strength (mcg) | In milligrams | In grams |
|---|---|---|
| 25 mcg | 0.025 mg | 0.000025 g |
| 50 mcg | 0.05 mg | 0.00005 g |
| 100 mcg | 0.1 mg | 0.0001 g |
| 200 mcg | 0.2 mg | 0.0002 g |
| 500 mcg | 0.5 mg | 0.0005 g |
Confusing mcg with mg here misstates the amount a thousandfold, which is why labels spell out mcg rather than using the µ symbol. The reasoning is covered in how pharmacists and nurses convert dosages safely.
When two labels disagree
- 1Convert both figures to the same unit before comparing anything.
- 2Check whether the figure is per tablet or per measured volume of liquid.
- 3Check the unit itself — mg, mcg and g look similar at speed.
- 4If the two still do not match, do not resolve it yourself. Ask the pharmacy.
Quick facts
- 500 mg = 0.5 g; 250 mg = 0.25 g; 1,000 mg = 1 g.
- Two 500 mg tablets contain 1 g of active ingredient in total.
- 1,000 mcg = 1 mg — a thousandth of the milligram figure.
- A tablet weighs more than its stated strength; the label describes the active ingredient only.
- Unit conversion never determines whether a dose is correct.
The full searchable table covering every commonly looked-up value is on the conversion chart page.
About this article
Written and maintained by the Milligrams to Grams editorial team. Every conversion figure in this article is generated with the same exact-decimal engine that powers the site's calculator, and is verified by an automated test suite rather than typed by hand. Read more about our methodology and accuracy standards.